We begin our review of the AMS 2750H;

Definitions:

• There are 5 changes in total. This number is one tenth of the total changes. I would like to state two definitions that I find important here. There are clearer sentences and expressions in the definitions of sensor (thermocouple) and expendable and non-expendable sensors.

Most importantly, when you protect an expandable sensor from the furnace atmosphere by putting it in a cover, this does not make it non-expandable. The standard now clearly explains this.

• Table 3 has a change bar due to change in definitions.

• Sensor Calibration (see 3.1.4.6 and Table 5)

Clarified the wording regarding 140 °C steps in sensor calibration.

• SAT and TUS Sensor Reuse (see 3.1.7.4 and 3.1.7.5)

The examples given here have been renewed with clearer expression.

• Main (base) Metal Load Sensors (see 3.1.10.3)

When sensors are replaced after a single use, the sensor batch number must be recorded and traceable to the load. Previously, there was no such requirement.

• General Instrumentation Requirements (see 3.2.1.4.1, 3.2.1.5 and Table 7)

For heat treatments where the time at temperature is less than 6 minutes, data collection will be more frequent than once per minute. This was at least 6 logging points for 10 minutes on the AMS 2750G.

• Control, Recording and Overtemperature Instruments (see 3.2.3.4, 3.2.3.5, 3.2.3.16 and 3.2.3.18)

The two separate examples given have been renewed.

• Instrument Calibration Results and Records (see 3.2.5.1)

In the section explaining calibration labels, the sentence was written in a different way for the same purpose.

• General Instrument Correction and Change Offset Requirements (see 3.2.6.1.2 and 3.2.6.1.8

There was a typo in this article. Although it said that the maximum cumulative offset that can be given to a furnace cannot exceed the TUS tolerance of that furnace, the given example showed half of it. They corrected this.

• Heat Treatment Equipment (see 3.3.7)

In evaluating multi-zone furnaces smaller than 6.4 cubic meters as a single zone, the number of over-temp sensors that were not included in the old text has been added.

• General SAT Requirements (see Table 11, Table 12, and 3.4.1.2.1)

In the relevant table, type D has been added to the instrumentation of Class 6 furnaces. In the old version there was only E. In addition, the special limit deviation has been removed.

• Conducting the SAT (see 3.4.2.2)

The requirement to perform SAT on all temperature measurement systems before heat treatment equipment that is out of service due to missing the calibration interval is included in production has been written more clearly.

• Alternative SAT Frequency (see 3.4.8.3)

Here, the furnace control sensor to which the control range is connected and the use of different reel type thermocouples are made more detailed and strict.

• SAT Disclaimer (see 3.4.9.6.3)

• SAT Difference Pass/Fail Requirements (see 3.4.10.4)

• Comparative SAT (see 3.4.11.1.e)

• Part furnace class, instrumentation type and internal TUS (see Table 15)

Find in the table D added to the instrumentation of Class 6 furnaces.

• Raw material furnace class, instrumentation type and internal TUS (see Table 16)

• Initial TUS Temperatures (see 3.5.2.4)

• TUS Requirements for Batch Furnaces, Salt Baths, Controlled Temperature Liquid Baths, and Fluidized Bed Furnaces (Except Controlled Temperature Quench Baths) (see Table 17)

• TUS Data Collection (see 3.5.10.1 and 3.5.10.2)

Since TUS data collection starts at a temperature below 55 °C, salt baths and ovens where TUS is performed for a single temperature have been omitted. It seems to me that this situation has not been explained clearly. What I understand is that there is now a longer recording requirement.

• Displacement of Hot or Cold Sensor Recording Sensors for Type A and C Instrumentation (see 3.5.15.2)

• Radiation Research (see 3.5.17, 3.5.17.1 and 3.5.17.2)

• TUS Range Deviations (see 3.5.18)

• Rounding (see 3.8)

The sentence "Rounding methods used in commercial spreadsheet programs are also acceptable" in AMS 2750G has been removed.

• Quality Assurance Provisions (see 4.2, 4.4 and Table 22).

• Deleted Zener Voltage Reference (was 3.5.87)